Leak Detection Equipment Tank Tightness Testing Ed Kubinsky Crompco

Tightness Testing Why Is Tank Tightness Testing Necessary? Satisfy Leak Detection Requirements (along with Inventory Control) Start-ups (contractor or owner request) SIR failure or inconclusive results Sudden release Tank taking on water

Tightness Testing Why Is Tank Tightness Testing Necessary? Accident Request by a regulatory authority ATG Failure Property Transfer Unexplained loss of product

Tank Tightness Testing Features: Some tightness test methods are “volumetric” methods in which the change in product level is measured very precisely in milliliters or thousandths of an inch.

Tank Tightness Testing Features: With non-volumetric underfill vacuum tests, the tester listens for sounds while the tank is under vacuum to determine whether or not the tank is leaking. A water sensor is used to measure any water ingress during the test.

Tightness Testing Tank Tightness Testing Procedures: Water table measurements and calculations are made in order to determine the length of the test and the amount of vacuum that must be applied. The water sensor must be used if the tank is submersed in water or if the tank is DW with brine in the interstitial space.

Tightness Testing Tank Tightness Testing Procedures: Once the required vacuum is achieved, the technician listens for both ullage leaks (hissing sounds) and leaks below the product level (bubble signatures). The technician also monitors the water sensor for signs of water ingress.

Tank Tightness Testing Features: Some methods require all of the measurements and calculations to be made by the tester. Other methods are highly automated. Once the tester sets up the equipment, a computer controls the measurement and analysis.

Tank Tightness Testing Features: Tanks must be taken out of service for tightness testing. The downtime depends on the test method and issues encountered during testing.

Tank Tightness Testing Features: Some methods require that tanks be filled to certain product levels. Check with your testing company to find out the requirements for their tank tightness method.

Tightness Testing Other considerations: Used primarily on USTs no more than 30,000 gallons in capacity.

Tightness Testing Other considerations: Test method, procedure, equipment and experienced personnel are all very important factors in a successful tank tightness test. Therefore:

Tightness Testing Make sure that your tester has been certified by the equipment manufacturer. Make sure that equipment being used by the tester has been certified and calibrated as well.

Tank Tightness Testing Using the EZY-3 Locator Plus (Estabrook’s Inc.)

Individual Certification Required Technicians must attend manufacturer training on the equipment and then renew their certification every 2 years.

Annual Equipment Calibration/Certification Required Each piece of equipment used must be sent back to the manufacturer annually for calibration and certification including: Acoustic Signal Processor Microphones Water Sensors Water Sensor displays Digital Pressure Sensors Analog Vacuum Gauges

Tank Tightness Testing – Understanding the Listing 3rd Party Listing of the EZY-3 Locator Plus Method is 3rd Party Approved by Ken Wilcox, meets US EPA tank tightness testing criteria to detect a .1 gph leak and is currently listed on the NWGLDE website: http://www.nwglde.org/evals/estabrook_ezy_check_d.html Non-Volumetric/Underfill Testing Technology Vacuum method using acoustic signal processor and microphone to determine tank integrity by the technician audibly listening for a leak. The amount of vacuum pulled on the tank in order to properly test the tank is dependent on site specific conditions including the height of product in the tank (inches), weight of fuel being tested (psi) and water table surrounding the tank

NWGLDE Listing Discussion

EZY-3 Locator Plus Operation Tank must be shut down while being tested Acoustic portion of the test takes only minutes to perform unless AHJ requires minimum test periods (background & test) Single wall tanks in a dry excavation and double wall tanks with a dry interstitial space can be tested rather quickly If water table exists on a single wall tank or if testing a double wall tank with a brine-filled interstitial area, test period must be extended by performing a water intrusion test in addition to the acoustic test This method tests both the wetted and dry portion of the tank

PRINCIPLE OF OPERATION EZY 3 LOCATOR PLUS NON-VOLUMETRIC TANK TESTING The testing instrumentation provided to the technician yields four very important bits of information on the underground tank. • An acoustic signal, which reveals “no” sound, and/or “no” water intrusion indicating a tight tank. • A leak in the ullage (dry) portion of the tank that reveals a “hiss” sound. • A leak below liquid level (wet) portion of the tank that reveals a “bubbling” sound. • The amount of water intrusion due to a leak.

Pros and Cons of the Method Completely dependent upon the technician’s discretion Can test tanks with minimal down time for the owner Very accurate in the hands of a good technician SW tanks in a dry excavation or DW tanks with dry interstitial can be tested quickly and accurately Cons: Completely dependent upon the technician’s discretion Potential problems associated with testing SW tanks containing ethanol blended fuel when a water table is above tank bottom or DW tanks with brine-filled interstitial areas, or E-85 tanks Can be disastrous in the hands of a poor or unethical technician

Documentation Required by the Manufacturer for a Test to be Considered Valid (Test Report)